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At least 613 records · Page 34

Use of Climate Change Projections for Resilience Planning in Rio de Janeiro, Brazil

In this study we use three different methodologies to document and compare temperature and precipitation projections for the city of Rio de Janeiro (RJ) over the 21st century. It aims to explore in what way the differences and similarities of those methodologies and their outcomes support the incorporation of climate risks in urban planning and improve effective urban climate change governance. We compared the projections for RJ from the Eta Regional Climate Model from the Brazilian National Institute for Space Research nested in two Hadley Center Global Climate Models (GCMs) (Eta-HadCM3 method and Eta-HadGEM2-ES method) and 33 GCMs from the Coupled Model Intercomparison Project Phase 5 multi-model dataset (Urban Climate Change Research Network - UCCRN method). The three methods showed increasing temperatures for RJ at the end of the century. Precipitation projections span a 13% decrease to a 12% increase when using the UCCRN method or are reduced between 0.4 and 0.5%, when using the Eta-HadGEM2-ES method. However, the middle range of the projections from UCCRN and Eta-HadGEM2-ES is similar. The three methods project an increase of warm days and nights and a decrease of cold days and nights. Nevertheless, although the directions of change are the same applying the three methods, the magnitude differs when considering warm and cold nights. Hence, city stakeholders are better informed when we apply different projection methods as it gives them the opportunity to consider the level of risk they are willing to bear in the future. We observed that defining climate change projections on the city scale based on clear communication and an interactive process between scientists and stakeholders can be used to inform citywide adaptation strategies and sector-specific uses, as well as promote urban climate risk governance.

urban governance and management↗

A New Vision and A More Rational Process Will Advance Space Life Support Through Better Projects

Many space life support assumptions are obviously mistaken but they are generally accepted because they mutually support each other and because they advance a mistaken futuristic vision of closed human ecosystems in space. Many projects have been mistakenly selected to increase life support system closure or reduce launch mass in order to implement this impractical vision. Project members rarely challenge their project’s assumptions and guiding vision. Systems engineering including cost, reliability, risk, and system trade-offs has been very strongly discouraged to prevent rational criticism of these dubious assumptions, the projects, and the ecosystem vision. A more realistic vision can define better near term life support goals and future aspirations that will improve mission support and increase public interest. Given more realistic goals, it will be possible to develop effective technical alternatives, use open rational project selection methods, conduct professional project management, and make swifter progress in the inevitable human advance into space. The current unworkable human space settlement scenario involves moon visits and permanent bases, zero gravity trips to Mars, Mars visits and bases, all leading to extensive human settlements on the moon and Mars. This is unrealistic because the moon and Mars have less than Earth normal gravity and high radiation that can seriously damage human health. A better alternative would use rotating space colonies that produce Earth gravity and are radiation shielded. The attractive fantasy of reproducing terrestrial ecology in space should be replaced by the idea of building a closed system based on advancing technology such as artificial photosynthesis. Past mistaken projects include growing plants for food to replicate terrestrial food sources, recovering small amounts of water from difficult to process waste to achieve high system closure, and using newly designed, lighter, but unreliable hardware to reduce launch mass. The political process supporting the false assumptions, projects, and vision has deliberately prevented the usual systems engineering and cost-benefit analysis. We are going to do much better.

Harry W. Jones↗

The Next Generation Radioisotope Thermoelectric Generator Project - Overview and Progress Status

The Next Generation Radioisotope Thermoelectric Generator (Next Gen RTG) Project is a spaceflight system project within NASA’s Radioisotope Power Systems (RPS) Program. The project, in partnership with the Idaho National Laboratory (INL) / Battelle Energy Alliance (BEA), will build and deliver an unfueled, flight qualified Radioisotope Thermoelectric Generator (RTG) system based on RPS Program needs. The Next Gen RTG Project aims to assure the availability of high-power, vacuum-rated RTGs to enable future deep space missions. The Project team is developing that capability through a multi-phase effort that leverages the heritage General Purpose Heat Source - RTG (GPHS-RTG) design and available legacy hardware. The Project’s primary aim is to re-establish the capability to manufacture a silicon germanium (SiGe) unicouple based thermoelectric converter and associated hardware with minimal changes to the heritage GPHS-RTG design. The project will also refurbish the GPHS-RTG Flight Unit #5 (F-5) located at INL and verify its compliance with heritage GPHS-RTG requirements. This paper will detail the project’s plans for the development of these systems. Management approaches, technical challenges, and risks will also be discussed.

Radioisotope↗

Mountaineer Commercial Scale Carbon Capture and Storage Project Topical Report: Preliminary Public Design Report

This Preliminary Public Design Report consolidates for public use nonproprietary design information on the Mountaineer Commercial Scale Carbon Capture & Storage project. The report is based on the preliminary design information developed during the Phase I - Project Definition Phase, spanning the time period of February 1, 2010 through September 30, 2011. The report includes descriptions and/or discussions for: (1) DOE's Clean Coal Power Initiative, overall project & Phase I objectives, and the historical evolution of DOE and American Electric Power (AEP) sponsored projects leading to the current project; (2) Alstom's Chilled Ammonia Process (CAP) carbon capture retrofit technology and the carbon storage and monitoring system; (3) AEP's retrofit approach in terms of plant operational and integration philosophy; (4) The process island equipment and balance of plant systems for the CAP technology; (5) The carbon storage system, addressing injection wells, monitoring wells, system monitoring and controls logic philosophy; (6) Overall project estimate that includes the overnight cost estimate, cost escalation for future year expenditures, and major project risks that factored into the development of the risk based contingency; and (7) AEP's decision to suspend further work on the project at the end of Phase I, notwithstanding its assessment that the Alstom CAP technology is ready for commercial demonstration at the intended scale.

01 COAL, LIGNITE, AND PEAT↗

Texas Clean Energy Project: Topical Report, Phase 1 - February 2010-December 2012

Summit Texas Clean Energy, LLC (STCE) is developing the Texas Clean Energy Project (TCEP or the project) to be located near Penwell, Texas. The TCEP will include an Integrated Gasification Combined Cycle (IGCC) plant with a nameplate capacity of 400 megawatts electric (MWe), combined with the production of urea fertilizer and the capture, utilization and storage of carbon dioxide (CO 2 ) sold commercially for regional use in enhanced oil recovery (EOR) in the Permian Basin of west Texas. The TCEP will utilize coal gasification technology to convert Powder River Basin subbituminous coal delivered by rail from Wyoming into a synthetic gas (syngas) which will be cleaned and further treated so that at least 90 percent of the overall carbon entering the facility will be captured. The clean syngas will then be divided into two high-hydrogen (H 2 ) concentration streams, one of which will be combusted as a fuel in a combined cycle power block for power generation and the other converted into urea fertilizer for commercial sale. The captured CO 2 will be divided into two streams: one will be used in producing the urea fertilizer and the other will be compressed for transport by pipeline for offsite use in EOR and permanent underground sequestration. The TCEP was selected by the U.S. Department of Energy (DOE) Office of Fossil Energy (FE) for cost-shared co-funded financial assistance under Round 3 of its Clean Coal Power Initiative (CCPI). A portion of this financial assistance was budgeted and provided for initial development, permitting and design activities. STCE and the DOE executed a Cooperative Agreement dated January 29, 2010, which defined the objectives of the project for all phases. During Phase 1, STCE conducted and completed all objectives defined in the initial development, permitting and design portions of the Cooperative Agreement. This topical report summarizes all work associated with the project objectives, and additional work required to complete the financing of the project. In general, STCE completed project definition, a front-end, engineering and design study (FEED), applied for and received its Record of Decision (ROD) associated with the NEPA requirements summarized in a detailed Environmental Impact Statement. A topical report covering the results of the FEED is the subject of a separate report submitted to the DOE on January 26, 2012. References to the FEED report are contained herein. In December 2011, STCE executed fixed-price turnkey EPC contracts and a long-term O&M agreement with industry-leading contractors.. Other work completed during Phase 1 includes execution of all major commercial input and offtake agreements. STCE negotiated long-term agreements for power, CO 2 and urea offtake. A contract for the purchase of coal feedstock from Cloud Peak Energy’s Cordero Rojo mine was executed, as well as a memorandum of understanding with the Union Pacific Railroad (UPRR) for delivery of the coal to the TCEP site. An MOU for natural gas supply was completed with ONEOK, and a long-term water supply agreement was completed with a private landowner. In addition, STCE secured options for easements and rights-of-way, completed a transmission study, executed an interconnection agreement and devoted substantial effort to debt and conventional and tax equity structuring to position the Project for project financing, currently scheduled for closing on December 31, 2012.

Mattes, Karl↗

Decision Point 3 of Statement of Project Objectives (SOPO) “Recovery Act: Development of ITM Oxygen Technology for Integration with Advanced Industrial Systems”

Air Products is carrying out a scope of work under Phase 5 of the ITM Oxygen Cooperative Agreement to design, build, and operate a ceramic membrane fabrication facility (the -CerFabII) to enable production of membrane modules to supply a conceptual 2000 ton per day (TPD) ITM Oxygen facility (the -ITM Oxygen Development FacilityII), and to perform supporting development tasks in materials development and engineering development toward industrial, carbon capture and sequestration applications. Air Products is executing this project under the American Recovery and Reinvestment Act (ARRA) with the objective to accelerate the adoption of ITM Oxygen technology to help meet the country’s goals for deploying clean power plants. The objective of this Topical Report is to address the requirements of Decision Point 3 (DP3), which pertains to the status of all Tasks within Phase 5 and most notably the project status of the CerFab (Task 30) prior to authorization of funds for equipment purchase and construction of the facility. The intent of the DP3 is to provide the opportunity for DOE-NETL to review the status of these tasks and to make recommendations on forward project direction, including a recommendation to pass into Budget Period 8. In the area of Materials Development, Air Products has specified a high pressure dilatometer system which will enable measurements of material expansion of ITM ceramic compounds at very high oxygen partial pressures consistent with CCS applications. Under Task 28.2, subcontractor Ceramatec has made significant progress since DP2 in materials selection and process development and improvement for advanced architecture module fabrication. Ceramatec has determined a materials specification, and has selected a process for making the material. Ceramatec has further developed and selected the process for applying the membrane to unsintered advanced architecture wafers with a Two Step process. Ceramatec has built submodules meeting leak rate specifications and intact 1-TPD modules compromised of advanced architecture components. Equipment and processes required for implementation of the advanced architecture design in the CerFab have been identified and are included in the Task 30 scope of equipment supply. Under Task 29.0, Air Products has developed conceptual ideas for implementation of ITM Oxygen in a 2000 TPD test unit. These concepts are proposed for scale up of the ITM technology to large scale with reduced commercial risk. Under Task 30, Air Products and Ceramatec have collaborated to re-design the CerFab process with the advanced architecture wafer production process as primary, and laid out the new process in the Tooele building; the required process equipment have been specified. The project team updated the project cost and schedule estimates, including all environmental permit schedules. The team also re-assessed project risk and costs for the commissioning and operating phases of the program. Newly projected costs for the CerFab, for which details are provided here as attachments, indicate a savings of approximately $100,000 relative to the original estimate at the time of Phase 5 contract definitization. However, an assessment of risks associated with the equipment, process, and operations of the CerFab indicate that approximately $2.9 million of costs should be expected to address various issues in the project. In addition, $1.6 million of additional spending is expected relative to the original estimate to operate the facility during Task 30.2. Air Products proposes a plan to re-direct funds from Tasks 28, 29, and 31 to Task 30 as necessary to allow the CerFab to meet the Phase 5 program objectives.

Armstrong, Phillip↗

Program Benefits Guidance: Analysis of Benefits Associated with Projects and Technologies Supported by the Alternative and Renewable Fuel and Vehicle Technology Program

The Alternative and Renewable Fuel and Vehicle Technologies Program (ARFVTP) supports a wide range of alternative, low-carbon fuel and vehicle projects in California. This report focuses on two types of ARFVTP benefits. Expected benefits reflect successful deployment of vehicles and fuels supported through program projects. Market transformation benefits represent benefits resulting from project influences on future market conditions to accelerated technology adoption rates. Data collected directly from ARFVTP projects funded from 2009 to first quarter 2014 are used as inputs to the benefits analysis, where possible. Expected benefit estimation methods rely primarily upon project-level data and result in year single-point estimates within the 2011 to 2025 analysis period. Results suggest that the 178 projects evaluated for expected benefits, representing an investment of $351.3 million in ARFVTP funds, could result in a reduction in petroleum fuel use by 236 million gallons per year and greenhouse gases (GHGs) by 1.7 million metric tonnes carbon dioxide equivalent (MMTCO2e) per year by 2025. Market transformation benefits are described as accruing in addition to expected benefits. They are inherently more uncertain and theoretical than expected benefits, and are therefore reported as high and low ranges, with results suggesting reductions of 1.1 MMTCO2e to 2.5 MMTCO2e per year in GHG reductions and 102 million to 330 million gallons per year in petroleum fuel reductions by 2025. Taking both benefit types into account, results suggest that ARFVTP projects have the potential to make substantial progress toward meeting California's long-term GHG and petroleum fuel use reduction goals. As additional project data become available and market success with alternative and renewable fuels and vehicles grows, the analytic framework relied upon to develop these estimates will become more rigorous and will have a greater capacity to inform future ARFVTP activities.

25 ENERGY STORAGE↗

Cost benefit analysis for smart grid projects

The U.S. is unusual in that a definition of the term “smart grid” was written into legislation, appearing in the Energy Independence and Security Act (2007). When the recession called for stimulus spending and the American Recovery and Reinvestment Act (ARRA, 2009) was passed, a framework already existed for identification of smart grid projects. About $4.5B of the U.S. Department of Energy’s (U.S. DOE’s) $37B allocation from ARRA was directed to smart grid projects of two types, investment grants and demonstrations. Matching funds from other sources more than doubled the total value of ARRA-funded smart grid projects. The Smart Grid Investment Grant Program (SGIG) consumed all but $620M of the ARRA funds, which was available for the 32 projects in the Smart Grid Demonstration Program (SGDP, or demonstrations). Given the economic potential of these projects and the substantial investments required, there was keen interest in estimating the benefits of the projects (i.e., quantifying and monetizing the performance of smart grid technologies). Common method development and application, data collection, and analysis to calculate and publicize the benefits were central objectives of the program. For this purpose standard methods and a software tool, the Smart Grid Computational Tool (SGCT), were developed by U.S. DOE and a spreadsheet model was made freely available to grantees and other analysts. The methodology was intended to define smart grid technologies or assets, the mechanisms by which they generate functions, their impacts and, ultimately, their benefits. The SGCT and its application to the Demonstration Projects are described, and actual projects in Southern California and in China are selected to test and illustrate the tool. The usefulness of the methodology and tool for international analyses is then assessed.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Accelerating the Whiteshell Laboratories Decommissioning Through the Implementation of a Projectized and Delivery-Focused Organization - 13074

Whiteshell Laboratories (WL) is a nuclear research site in Canada that was commissioned in 1964 by Atomic Energy of Canada Limited. It covers a total area of approximately 4,375 hectares (10,800 acres) and includes the main campus site, the Waste Management Area (WMA) and outer areas of land identified as not used for or impacted by nuclear development or operations. The WL site employed up to 1100 staff. Site activities included the successful operation of a 60 MW organic liquid-cooled research reactor from 1965 to 1985, and various research programs including reactor safety research, small reactor development, fuel development, biophysics and radiation applications, as well as work under the Canadian Nuclear Fuel Waste Management Program. In 1997, AECL made a business decision to discontinue research programs and operations at WL, and obtained government concurrence in 1998. The Nuclear Legacy Liabilities Program (NLLP) was established in 2006 by the Canadian Government to remediate nuclear legacy liabilities in a safe and cost effective manner, including the WL site. The NLLP is being implemented by AECL under the governance of a Natural Resources Canada (NRCan)/AECL Joint Oversight Committee (JOC). Significant progress has since been made, and the WL site currently holds the only Canadian Nuclear Safety Commission (CNSC) nuclear research site decommissioning license in Canada. The current decommissioning license is in place until the end of 2018. The present schedule planned for main campus decommissioning is 30 years (to 2037), followed by institutional control of the WMA until a National plan is implemented for the long-term management of nuclear waste. There is an impetus to advance work and complete decommissioning sooner. To accomplish this, AECL has added significant resources, reorganized and moved to a projectized environment. This presentation outlines changes made to the organization, the tools implemented to foster projectization, and the benefits and positive impacts on schedule and delivery. A revised organizational structure was implemented in two phases, starting 2011 April 1, to align WL staff with the common goal of decommissioning the site through the direction of the WL Decommissioning Project General Manager. On 2011 September 1, the second phase of the reorganization was implemented and WL Decommissioning staff was organized under five Divisions: Programs and Regulatory Compliance, General Site Services, Decommissioning Strategic Planning, Nuclear Facilities and Project Delivery. A new Mission, Vision and Objectives were developed for the project, and several productivity enhancements are being implemented. These include the use of an integrated and fully re-sourced Site Wide Schedule that is updated and reviewed at Plan-of-the-Week meetings, improved work distribution throughout the year, eliminating scheduling 'push' mentality, project scoreboards, work planning implementation, lean practices and various process improvement initiatives. A revised Strategic Plan is under development that reflects the improved project delivery capabilities. As a result of these initiatives, and a culture change towards a projectized approach, the decommissioning schedule will be advanced by approximately 10 years. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Nevada National Security Site Industrial Sites Project Closeout - 12498

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office is responsible for environmental restoration (ER) at the Nevada National Security Site (NNSS). This includes remediation at Industrial Sites where past nuclear testing activities and activities that supported nuclear testing may have or are known to have resulted in the release of contaminants into the environment. Industrial Sites at the NNSS have included nuclear facilities that supported the nuclear rocket/missile development programs, gas stations, landfills, spill sites, ordnance sites, and numerous other waste disposal and release sites. The NNSS Industrial Sites activities neared completion at the end of fiscal year 2011 while other activities required under the Federal Facility Agreement and Consent Order (FFACO) and part of the same NNSS ER Project are forecasted to extend to 2027 or beyond. With the majority of Industrial Sites corrective action units (CAUs) completed (more than 250 CAUs and over 1,800 corrective action sites), it was determined that an activity closeout process should be implemented to ensure that the work completed over the past 15 years is well documented in a comprehensive and concise summary. While the process used to close each individual CAU is described in approved documents, no single document describes in summary fashion the work completed to close the many individual Industrial Sites. The activity closeout process will be used to develop an Industrial Sites closeout document that describes these years of work. This document will summarize the number of Industrial Sites closed under the FFACO and provide general descriptions of projects, contaminants removed, and sites closed in place with corresponding Use Restrictions. Other pertinent information related to Industrial Sites work such as the project history, closure decisions, historical declarations, remediation strategies, and final CAU status will be included in the closeout document, along with a table listing each CAU and corresponding corrective action sites within each CAU. Using this process of conducting the activity closeout and developing a closeout document may prove useful for other ER projects within the DOE complex in describing how a long period of ER can be summarized in a single document. The NNSS Industrial Sites activities were completed over the span of 15 years and involved the investigation, cleanup or Use Restriction, and closure of more than 260 CAUs and over 1,800 sites. These activities will conclude in FY 2012 (with the exception of one CAU). In order to capture the work completed over this length of time and document decisions made during the activities, a closeout effort was initiated. The closeout will review the work conducted during the Industrial Sites activities and produce a single document that summarizes Industrial Sites activities. This closeout is being conducted at an interim stage in the overall NNSA/NSO ER Project since the Soils and UGTA activities will continue for a number of years, but the completion of the Industrial Sites project warrants conducting a closeout now while personnel are available and information is still current. The process followed by NNSA/NSO in conducing project closeout for the Industrial Sites portion of the ER program may prove useful within the DOE complex in demonstrating how a large ER project can be summarized. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

The Port Hope Area Initiative's Port Granby Project: From Planning to Execution - 17451

The Port Hope Area Initiative's Port Granby Project involves the construction of a new, secure long-term waste management facility (LTWMF) and supporting infrastructure, and the excavation and relocation of some 450,000 m{sup 3} of LLRW and marginally contaminated soil from the former Port Granby Waste Management Facility (PGWMF) to the newly constructed LTWMF. Presented is an overview of the Port Granby Project and a description of the planning needed to execute the project successfully. A comprehensive suite of approximately 40 pre-construction submittals were developed and submitted for review and approval by Canadian Nuclear Laboratories (CNL), the project authority. Importantly, comprehensive training programs were developed and implemented to ensure all project staff fully understood the scope of the planning documents (covering such things as Quality Control, Environmental Monitoring, Radiation Protection, Dust Management, Noise, Radiation Protection etc.) and possess the appropriate competencies for completing the work to which they have been assigned. The effective planning that has been invested in the Port Granby project, from initial design to project planning and implementation, has allowed this complex project to proceed with minimal difficulty. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Progress updates for the Hanford waste treatment and immobilization plant project - 15593

The Waste Treatment and Immobilization Plant (WTP) Project is vital to the U.S. Department of Energy's (DOE) mission to clean up radioactive waste at the Hanford Site in southeastern Washington State. The overall WTP Project objective is to design, build, and commission the facilities and systems that will treat and immobilize approximately 211 983 m{sup 3} (56 million gallons) of radioactive waste stored in 177 underground storage tanks. The combination of technologies in the WTP makes it a first-of-a-kind facility at a scale larger than ever built for radioactive waste processing. In recent years, the project has encountered issues that affected project design completion, especially in the Pretreatment and High-Level Waste Facilities. These included technical issues, changes in requirements, changes in funding, weaknesses in the nuclear supply chain, identification of new hazards, and new information about the tank waste. The combination of these issues led to a suspension of construction of the Pretreatment Facility and a partial suspension of construction of the High-Level Waste Facility in mid-2012. Since then, the WTP Project has made significant progress in establishing and implementing a strategy for resolving these issues. This strategy focuses on resuming full production work in a sequence that fully supports the DOE plan for a phased approach for starting treatment of the Hanford tank waste, beginning with the low-activity waste streams. Concurrent with the technical and programmatic issues, the DOE Office of River Protection has made numerous changes in the processes it uses to manage and oversee the WTP Project. These changes have had a beneficial impact on the progress the project has made in establishing a path forward for resuming production activities, and on planning for the necessary contract and baseline changes needed to complete the project. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Systematic Analysis of Drivers and Barriers of Cross-Sectorial Learning Between Nuclear and Oil and Gas Decommissioning Projects - 20139

Project and megaproject management in the energy sector have historically focused on the planning and delivery of the construction of infrastructure. Therefore, policies are predominantly oriented to support the construction of infrastructure rather than its decommissioning. However, globally, several facilities have reached (or will soon reach) their end-of-life and need to be decommissioned. These facilities span across the energy sector, including nuclear power plants and oil and gas rigs, whose decommissioning present unprecedented techno-socio-economic challenges. Moreover, globally, their decommissioning cost is estimated to reach hundreds of billions of US dollars and this budget keeps increasing, with limited knowledge-transfer across industries to mitigate the spiraling increase of this figure. Cross-sectorial knowledge-transfer is a way to tackle this matter and improve the planning and delivery of decommissioning and waste management projects. The aim of this research is to build a road-map based on cross-sectorial industrial experience, designed to promote the sharing of good practices between projects both within and across industries dealing with major decommissioning and waste management challenges. To reach this aim, the tacit knowledge of senior practitioners on several large scale nuclear and oil and gas decommissioning projects is made explicit by the means of semi-structured interviews, systematically analyzed through directed content analysis. The results of this analysis include a list of good practices that could and should be transferred to nuclear decommissioning projects, including the need to promote the adoption of incentives explicitly linked to the project deliverables, and to develop long-term plans to support smooth transition from operations to decommissioning. Suggestions about how the knowledge-transfer can be promoted within and across organizations are also discussed. In this way, this research provides practical guidance for project managers and policymakers on how to support the planning and delivery of projects with improved performance. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Understanding uncertainties in projections of western North Pacific tropical cyclogenesis

Reliable projections of tropical cyclone (TC) activities in the western North Pacific (WNP) are crucial for climate policy-making in densely-populated coastal Asia. Existing projections, however, exhibit considerable uncertainties with unclear sources. Here, based on future projections by the latest Coupled Model Intercomparison Project Phase 6 climate models, we identify a new and prevailing source of uncertainty arising from different TC identification schemes. Notable differences in projections of detected TCs and empirical genesis potential indices are found to be caused by inconsistent changes in dynamic and thermodynamic environmental factors affecting TC formations. While model uncertainty holds the secondary importance, we show large potential in reducing it through improved model simulations of present-day TC characteristics. Internal variability noticeably impacts near-term projections of the WNP tropical cyclogenesis, while the relative contribution of scenario uncertainty remains small. Our findings provide valuable insights into model development and TC projections, thereby aiding in adaptation decisions.

54 ENVIRONMENTAL SCIENCES↗

Space–Time Least-Squares Petrov–Galerkin Projection for Nonlinear Model Reduction

This work proposes a space--time least-squares Petrov--Galerkin (ST-LSPG) projection method for model reduction of nonlinear dynamical systems. In contrast to typical nonlinear model-reduction methods that first apply (Petrov--)Galerkin projection in the spatial dimension and subsequently apply time integration to numerically resolve the resulting low-dimensional dynamical system, the proposed method applies projection in space and time simultaneously. To accomplish this, the method first introduces a low-dimensional space--time trial subspace, which can be obtained by computing tensor decompositions of state-snapshot data. The method then computes discrete-optimal approximations in this space--time trial subspace by minimizing the residual arising after time discretization over all space and time in a weighted $\ell^2$-norm. This norm can be defined to enable complexity reduction (i.e., hyper-reduction) in time, which leads to space--time collocation and space--time Gauss--Newton with Approximated Tensors (GNAT) variants of the ST-LSPG method. Advantages of the approach relative to typical spatial-projection-based nonlinear model reduction methods such as Galerkin projection and least-squares Petrov--Galerkin projection include a reduction of both the spatial and temporal dimensions of the dynamical system, and a priori error bounds that bound the solution error by the best space--time approximation error and whose stability constants exhibit slower growth in time. Numerical examples performed on model problems in fluid dynamics demonstrate the ability of the method to generate orders-of-magnitude computational savings relative to spatial-projection-based reduced-order models without sacrificing accuracy for a fixed spatio-temporal discretization.

97 MATHEMATICS AND COMPUTING↗

Bayesian Hierarchical Model Uncertainty Quantification for Future Hydroclimate Projections in Southern Hills-Gulf Region, USA

The study investigates the hierarchical uncertainty of multi-ensemble hydroclimate projections for the Southern Hills-Gulf region, USA, considering emission pathways and a global climate model (GCM) as two main sources of uncertainty. Forty projections of downscaled daily air temperature and precipitation from 2010 to 2099 under four emission pathways and ten CMIP5 GCMs are adopted for hydroclimate modeling via the HELP3 hydrologic model. This study focuses on evapotranspiration (ET), surface runoff, and groundwater recharge projections in this century. Climate projection uncertainty is characterized by the hierarchical Bayesian model averaging (HBMA) method, which segregates emission pathway uncertainty and climate model uncertainty. HBMA is able to derive ensemble means and standard deviations, arising from individual uncertainty sources, for ET, runoff, and recharge. The model results show that future recharge in the Southern Hills-Gulf region is more sensitive to different climate projections and exhibits higher variability than ET and runoff. Overall, ET is likely to increase and runoff is likely to decrease in this century given the current emission path scenarios. Runoff are predicted to have an 18% to 20% decrease and ET is predicted to have around a 3% increase throughout the century. Groundwater recharge is likely to increase in this century with a decreasing trend. Recharge would increase about 13% in the early century and will have only a 3% increase in the late century. All hydrological projections have increasing uncertainty towards the end of the century. The HBMA result suggests that the GCM uncertainty dominates the overall hydrological projection uncertainty in the early century and the mid-century. The emission pathway uncertainty becomes important in the late century.

54 ENVIRONMENTAL SCIENCES↗

Going South: Warnings from the Largest Project Engineering Failure in Modern History

NASA’s successful conduct of the Apollo Program greatly enhanced the prestige of the United States and remains broadly accepted as America’s gift “for all Mankind.” NASA’s Artemis Program to return humanity to the Moon promises to again reveal America’s leadership in this field. In preparation for the initiation of Artemis and its predecessor project Constellation, NASA thoroughly examined space program precedents. There remains, however, another relevant precedent which has not been examined in this context. Though this project involved technology radically different from that managed by NASA, its scope and environment in many ways parallel NASA’s large programs. This project was initiated by a private sector team that had, ten years before, successfully completed an effort that, at a cost of $275 billion (in 2021 USD), had stimulated new technology, had brought economic growth, had established their country as the world leader in engineering innovation, and, though it was a commercial success, had been broadly accepted as their nation’s gift “to all Mankind.” The new project was inspired by popular belief that private capital could again be marshalled to enhance national prestige and make yet another major contribution to the progress of Humanity. This new effort was predicted to require eight years and $258 billion. However, after the passage of nine years, achievement of only 45% complete on the baseline design, and expenditures 96% beyond the baseline cost, the project collapsed amid bankruptcy, political scandal, and criminal prosecution. While the private sector team that carried out this project was exceptionally well educated and experienced in the field, their efforts resulted in what remains (in terms of the money wasted) the largest project engineering failure in modern history. This paper examines what went wrong.

Project Management↗

Projections of future climate for U.S. national assessments: past, present, future

Climate assessments consolidate our understanding of possible future climate conditions as represented by climate projections, which are largely based on the output of global climate models. Over the past 30 years, the scientific insights gained from climate projections have been refined through model structural improvements, emerging constraints on climate feedbacks, and increased computational efficiency. Within the same period, the process of assessing and evaluating information from climate projections has become more defined and targeted to inform users. As the size and audience of climate assessments has expanded, the framing, relevancy, and accessibility of projections has become increasingly important. This paper reviews the use of climate projections in national climate assessments (NCA) while highlighting challenges and opportunities that have emerged over time. Reflections and lessons learned address the continuous process to understand the broadening assessment audience and evolving user needs. Insights for future NCA development include (1) identifying benchmarks and standards for evaluating downscaled datasets, (2) expanding efforts to gather research gaps and user needs to inform how climate projections are presented in the assessment (3) providing practitioner guidance on the use, interpretation, and reporting of climate projections and uncertainty to better inform decision-making.

Assessment↗